ASTM E83 is the ASTM practice for verifying and classifying extensometer systems used to measure strain during mechanical testing. The result is an extensometer class that defines the strains it can report with confidence. To select an extensometer class for your test method, talk with our team.
What ASTM E83 Covers
The practice checks how accurately an extensometer measures displacement over its gauge length. Known displacements from a reference device are compared with the extensometer output, and the fixed error and strain error determine the class.
Extensometer Classes
E83 defines several classes, from the tightest used for modulus and proof strength to wider classes for large-strain work:
| Class | Typical application |
|---|---|
| Class B-1 | Modulus and proof strength, where the smallest strains must be resolved |
| Class B-2 / C | General yield and elongation measurement |
| Class D / E | Large-strain measurements with wider tolerance |
Why Classification Matters
Tensile methods such as ASTM E8/E8M expect strain to be measured with an extensometer of a stated class. Using a class that is too wide for the property being reported, such as modulus, invalidates the result. E83 is the record that ties strain accuracy to the reported property.
Reading the Designation
Cited with a year suffix, such as ASTM E83-16. Confirm the edition before setting verification intervals and class requirements.
Related Standards
ISO 9513 is the ISO counterpart for extensometer calibration, ASTM E4 verifies the machine force system, and ASTM E8/E8M is a method that depends on classified extensometry.
Request a Quote
Need extensometers verified or selected for a method? Request a quote and our team will help you build a system matched to your strain range and extensometer class.
TensileMill CNC products for ASTM E83
Our specimen-preparation systems and testing equipment compatible with ASTM E83:
Electro Mechanical Universal Testing System 5 kN / 50 kN with Precision Load Cell
Electro-Mechanical UTM · 5 kN / 50 kN with Precision Load Cell
Electro Mechanical Universal Testing System 50kN / 1000kN with Precision Load Cell
Electro-Mechanical UTM · 50 kN / 1000 kN with Precision Load Cell
Servo-Hydraulic Universal Testing Machine (300 kN – 3000 kN)
Servo-Hydraulic UTM · 300 kN – 3000 kN
Precision Alignment Device (NADCAP-Ready Precision Fixture)
NADCAP-Ready Precision Alignment Fixture
Configure your ASTM E83 setup with TensileMill CNC
TensileMill CNC builds testing systems used across quality control, research, and production. For this work we supply load cells, alignment hardware, and the reference setups used for machine and extensometer verification. Share your material mix and throughput, and we will recommend a setup that fits ASTM E83.